perf: index return_against on delivery note (#38827)

There's a multi-column index but that's useful IFF all parts of column
are part of query.

return against on it's own is VERY unique because it's a primary key, we
don't need a multi-column index here.

erpnext/patches.txt

@@ -354,3 +354,4 @@ execute:frappe.db.set_single_value("Buying Settings", "project_update_frequency"
 execute:frappe.db.set_default("date_format", frappe.db.get_single_value("System Settings", "date_format"))
 # below migration patch should always run last
 erpnext.patches.v14_0.migrate_gl_to_payment_ledger
+erpnext.stock.doctype.delivery_note.patches.drop_unused_return_against_index

erpnext/stock/doctype/delivery_note/delivery_note.json

@@ -301,7 +301,8 @@
    "no_copy": 1,
    "options": "Delivery Note",
    "print_hide": 1,
-   "read_only": 1
+   "read_only": 1,
+   "search_index": 1
   },
   {
    "collapsible": 1,
@@ -1401,7 +1402,7 @@
  "idx": 146,
  "is_submittable": 1,
  "links": [],
- "modified": "2023-09-04 14:15:28.363184",
+ "modified": "2023-12-18 17:19:39.368239",
  "modified_by": "Administrator",
  "module": "Stock",
  "name": "Delivery Note",

erpnext/stock/doctype/delivery_note/delivery_note.py

@@ -1294,7 +1294,3 @@ def make_inter_company_transaction(doctype, source_name, target_doc=None):
 	)
 
 	return doclist
-
-
-def on_doctype_update():
-	frappe.db.add_index("Delivery Note", ["customer", "is_return", "return_against"])

erpnext/stock/doctype/delivery_note/patches/drop_unused_return_against_index.py

@@ -0,0 +1,15 @@
+import frappe
+
+
+def execute():
+	"""Drop unused return_against index"""
+
+	try:
+		frappe.db.sql_ddl(
+			"ALTER TABLE `tabDelivery Note` DROP INDEX `customer_is_return_return_against_index`"
+		)
+		frappe.db.sql_ddl(
+			"ALTER TABLE `tabPurchase Receipt` DROP INDEX `supplier_is_return_return_against_index`"
+		)
+	except Exception:
+		frappe.log_error("Failed to drop unused index")

erpnext/stock/doctype/purchase_receipt/purchase_receipt.json

@@ -289,7 +289,8 @@
    "no_copy": 1,
    "options": "Purchase Receipt",
    "print_hide": 1,
-   "read_only": 1
+   "read_only": 1,
+   "search_index": 1
   },
   {
    "fieldname": "section_addresses",
@@ -1251,7 +1252,7 @@
  "idx": 261,
  "is_submittable": 1,
  "links": [],
- "modified": "2023-11-28 13:14:15.243474",
+ "modified": "2023-12-18 17:26:41.279663",
  "modified_by": "Administrator",
  "module": "Stock",
  "name": "Purchase Receipt",

erpnext/stock/doctype/purchase_receipt/purchase_receipt.py

@@ -1360,10 +1360,6 @@ def get_item_account_wise_additional_cost(purchase_document):
 	return item_account_wise_cost
 
 
-def on_doctype_update():
-	frappe.db.add_index("Purchase Receipt", ["supplier", "is_return", "return_against"])
-
-
 @erpnext.allow_regional
 def update_regional_gl_entries(gl_list, doc):
 	return